The exploits that comex used to jailbreak the iOS could be used for other purposes, including delivering malicious payloads to grab control of iPhones, iPads and iPod Touches. All that would be necessary is for hackers to dupe users into visiting a malicious Web site or persuading them to click on a link in an e-mail or text message.

"Impressive. And dangerous," is how Mikko Hypponen, chief research officer at antivirus company F-Secure, described the exploit code on Twitter early today.

It may not be long before comex's work is turned into a weapon for attacks that gain "root" access, or complete control, of iPhones and iPads.

"@comex thanks, using it to make malicious s*** now," bragged someone identified as "MTWomg" on Twitter shortly after comex published the source code.

Noted Mac vulnerability researcher Dino Dai Zovi, co-author of The Mac Hackers Handbook, chimed in with a warning of his own. "Now that @comex released his jailbreak source, any bets on how long before it is ported to Metasploit?" Dai Zovi tweeted Wednesday.

Metasploit is the open-source penetration testing framework that some use as a hacking toolkit.

Apple did not patch 2007's first-generation iPhone or iPod Touch yesterday, delivering the update only to the iPhone 3G or later devices running the iOS 2.0 or later, and to the second-generation iPod Touch or later running iOS 2.1 or later. Lacking patches, the early models may be vulnerable to attack.

Also possibly at risk: Mac OS X. Like iOS, Apple's desktop operating system includes the FreeType font engine, which may be vulnerable to the same or a similar exploit.

And users who have used comex's code to jailbreak their iPhones have a decision to make. If they accept Wednesday's update, they lose the ability to install and run software not approved by Apple. But by ignoring the update, they may be victimized by future attacks based on the public code.

"We recommend that all iOS users, including those who have jailbroken their devices, would install the latest update now," Hypponen said in a blog post Wednesday.

Users can download the iOS update by connecting their iPhones, iPod Touches or iPads to their PCs or Macs, running iTunes, clicking on the device in the listing on the left and then clicking the "Check for Update" button.